Prominent altruists aren’t the people who have a larger care-o-meter, they’re the people who have learned not to trust their care-o-meters… Nobody has [a care-o-meter] capable of faithfully representing the scope of the world’s problems. But the fact that you can’t feel the caring doesn’t mean that you can’t do the caring.
Nate Soares
Now also posted to Less Wrong. (It hadn’t yet been when Luke quoted it above.)